369 lines
6.9 KiB
C
369 lines
6.9 KiB
C
/*
|
|
* NTP simulator engine - Harish Nair
|
|
* University of Delaware, 2001
|
|
*/
|
|
#include "ntpd.h"
|
|
#include "ntpsim.h"
|
|
|
|
/*
|
|
* Defines...
|
|
*/
|
|
#define SIM_TIME 86400 /* end simulation time */
|
|
#define NET_DLY .001 /* network delay */
|
|
#define PROC_DLY .001 /* processing delay */
|
|
#define BEEP_DLY 3600 /* beep interval (s) */
|
|
#define SLEW 500e-6 /* correction rate (PPM) */
|
|
|
|
/*
|
|
* Function pointers
|
|
*/
|
|
void (*funcPtr[]) (Node *, Event) = {
|
|
&ndbeep, &ndeclk, &ntptmr, &netpkt
|
|
};
|
|
|
|
|
|
/*
|
|
* ntpsim - initialize global variables and event queue and start
|
|
*/
|
|
int
|
|
ntpsim(
|
|
int argc,
|
|
char *argv[]
|
|
)
|
|
{
|
|
Event e;
|
|
double maxtime;
|
|
struct timeval seed;
|
|
|
|
/*
|
|
* Initialize the global node
|
|
*/
|
|
ntp_node.time = 0; /* simulation time */
|
|
ntp_node.sim_time = SIM_TIME; /* end simulation time (-S) */
|
|
ntp_node.ntp_time = 0; /* client disciplined time */
|
|
ntp_node.adj = 0; /* remaining time correction */
|
|
ntp_node.slew = SLEW; /* correction rate (-H) */
|
|
|
|
ntp_node.clk_time = 0; /* server time (-O) */
|
|
ntp_node.ferr = 0; /* frequency error (-T) */
|
|
ntp_node.fnse = 0; /* random walk noise (-W) */
|
|
ntp_node.ndly = NET_DLY; /* network delay (-Y) */
|
|
ntp_node.snse = 0; /* phase noise (-C) */
|
|
ntp_node.pdly = PROC_DLY; /* processing delay (-Z) */
|
|
ntp_node.bdly = BEEP_DLY; /* beep interval (-B) */
|
|
|
|
ntp_node.events = NULL;
|
|
ntp_node.rbuflist = NULL;
|
|
|
|
/*
|
|
* Initialize ntp variables
|
|
*/
|
|
initializing = 1;
|
|
init_auth();
|
|
init_util();
|
|
init_restrict();
|
|
init_mon();
|
|
init_timer();
|
|
init_lib();
|
|
init_random();
|
|
init_request();
|
|
init_control();
|
|
init_peer();
|
|
init_proto();
|
|
init_io();
|
|
init_loopfilter();
|
|
mon_start(MON_OFF);
|
|
getconfig(argc, argv);
|
|
initializing = 0;
|
|
|
|
/*
|
|
* Watch out here, we want the real time, not the silly stuff.
|
|
*/
|
|
gettimeofday(&seed, NULL);
|
|
srand48(seed.tv_usec);
|
|
|
|
/*
|
|
* Push a beep and timer interrupt on the queue
|
|
*/
|
|
push(event(0, BEEP), &ntp_node.events);
|
|
push(event(ntp_node.time + 1.0, TIMER), &ntp_node.events);
|
|
|
|
/*
|
|
* Pop the queue until nothing is left or time is exceeded
|
|
*/
|
|
maxtime = ntp_node.time + ntp_node.sim_time;
|
|
while (ntp_node.time <= maxtime && ntp_node.events != NULL ) {
|
|
e = pop(&ntp_node.events);
|
|
ndeclk(&ntp_node, e);
|
|
funcPtr[e.function](&ntp_node, e);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
|
|
/*
|
|
* Return an event
|
|
*/
|
|
Event
|
|
event(
|
|
double t,
|
|
funcTkn f
|
|
)
|
|
{
|
|
Event e;
|
|
|
|
e.time = t;
|
|
e.function = f;
|
|
return (e);
|
|
}
|
|
|
|
/*
|
|
* Create an event queue
|
|
*/
|
|
Queue
|
|
queue(
|
|
Event e,
|
|
Queue q
|
|
)
|
|
{
|
|
Queue ret;
|
|
|
|
if ((ret = (Queue)malloc(sizeof(struct List))) == NULL)
|
|
abortsim("queue-malloc");
|
|
ret->event = e;
|
|
ret->next = q;
|
|
return (ret);
|
|
}
|
|
|
|
|
|
/*
|
|
* Push an event into the event queue
|
|
*/
|
|
void push(
|
|
Event e,
|
|
Queue *qp
|
|
)
|
|
{
|
|
Queue *tmp = qp;
|
|
|
|
while (*tmp != NULL && ((*tmp)->event.time < e.time))
|
|
tmp = &((*tmp)->next);
|
|
*tmp = queue(e, (*tmp));
|
|
}
|
|
|
|
|
|
/*
|
|
* Pop the first event from the event queue
|
|
*/
|
|
Event
|
|
pop(
|
|
Queue *qp
|
|
)
|
|
{
|
|
Event ret;
|
|
Queue tmp;
|
|
|
|
tmp = *qp;
|
|
if (tmp == NULL)
|
|
abortsim("pop - empty queue");
|
|
ret = tmp->event;
|
|
*qp = tmp->next;
|
|
free(tmp);
|
|
return (ret);
|
|
}
|
|
|
|
|
|
/*
|
|
* Update clocks
|
|
*/
|
|
void
|
|
ndeclk(
|
|
Node *n,
|
|
Event e
|
|
)
|
|
{
|
|
node_clock(n, e.time);
|
|
}
|
|
|
|
|
|
/*
|
|
* Timer interrupt. Eventually, this results in calling the
|
|
* srvr_rplyi() routine below.
|
|
*/
|
|
void
|
|
ntptmr(
|
|
Node *n,
|
|
Event e
|
|
)
|
|
{
|
|
struct recvbuf *rbuf;
|
|
|
|
timer();
|
|
|
|
/*
|
|
* Process buffers received. They had better be in order by
|
|
* receive timestamp.
|
|
*/
|
|
while (n->rbuflist != NULL) {
|
|
rbuf = n->rbuflist;
|
|
n->rbuflist = rbuf->next;
|
|
(rbuf->receiver)(rbuf);
|
|
free(rbuf);
|
|
}
|
|
|
|
/*
|
|
* Arm the next timer interrupt.
|
|
*/
|
|
push(event(e.time + (1 << EVENT_TIMEOUT), TIMER), &n->events);
|
|
}
|
|
|
|
|
|
/*
|
|
* srvr_rply() - send packet
|
|
*/
|
|
int srvr_rply(
|
|
Node *n,
|
|
struct sockaddr_storage *dest,
|
|
struct interface *inter, struct pkt *rpkt
|
|
)
|
|
{
|
|
struct pkt xpkt;
|
|
struct recvbuf rbuf;
|
|
Event xvnt;
|
|
double dtemp, etemp;
|
|
|
|
/*
|
|
* Insert packet header values. We make this look like a
|
|
* stratum-1 server with a GPS clock, but nobody will ever
|
|
* notice that.
|
|
*/
|
|
xpkt.li_vn_mode = PKT_LI_VN_MODE(LEAP_NOWARNING, NTP_VERSION,
|
|
MODE_SERVER);
|
|
xpkt.stratum = STRATUM_TO_PKT(((u_char)1));
|
|
memcpy(&xpkt.refid, "GPS", 4);
|
|
xpkt.ppoll = rpkt->ppoll;
|
|
xpkt.precision = rpkt->precision;
|
|
xpkt.rootdelay = 0;
|
|
xpkt.rootdispersion = 0;
|
|
|
|
/*
|
|
* Insert the timestamps.
|
|
*/
|
|
xpkt.org = rpkt->xmt;
|
|
dtemp = poisson(n->ndly, n->snse); /* client->server delay */
|
|
DTOLFP(dtemp + n->clk_time, &xpkt.rec);
|
|
dtemp += poisson(n->pdly, 0); /* server delay */
|
|
DTOLFP(dtemp + n->clk_time, &xpkt.xmt);
|
|
xpkt.reftime = xpkt.xmt;
|
|
dtemp += poisson(n->ndly, n->snse); /* server->client delay */
|
|
|
|
/*
|
|
* Insert the I/O stuff.
|
|
*/
|
|
rbuf.receiver = receive;
|
|
get_systime(&rbuf.recv_time);
|
|
rbuf.recv_length = LEN_PKT_NOMAC;
|
|
rbuf.recv_pkt = xpkt;
|
|
memcpy(&rbuf.srcadr, dest, sizeof(struct sockaddr_storage));
|
|
memcpy(&rbuf.recv_srcadr, dest,
|
|
sizeof(struct sockaddr_storage));
|
|
if ((rbuf.dstadr = malloc(sizeof(struct interface))) == NULL)
|
|
abortsim("server-malloc");
|
|
memcpy(rbuf.dstadr, inter, sizeof(struct interface));
|
|
rbuf.next = NULL;
|
|
|
|
/*
|
|
* Very carefully predict the time of arrival for the received
|
|
* packet.
|
|
*/
|
|
LFPTOD(&xpkt.org, etemp);
|
|
etemp += dtemp;
|
|
xvnt = event(etemp, PACKET);
|
|
xvnt.rcv_buf = rbuf;
|
|
push(xvnt, &n->events);
|
|
return (0);
|
|
}
|
|
|
|
|
|
/*
|
|
* netpkt() - receive packet
|
|
*/
|
|
void
|
|
netpkt(
|
|
Node *n,
|
|
Event e
|
|
)
|
|
{
|
|
struct recvbuf *rbuf;
|
|
struct recvbuf *obuf;
|
|
|
|
/*
|
|
* Insert the packet on the receive queue and record the arrival
|
|
* time.
|
|
*/
|
|
if ((rbuf = malloc(sizeof(struct recvbuf))) == NULL)
|
|
abortsim("ntprcv-malloc");
|
|
memcpy(rbuf, &e.rcv_buf, sizeof(struct recvbuf));
|
|
rbuf->receiver = receive;
|
|
DTOLFP(n->ntp_time, &rbuf->recv_time);
|
|
rbuf->next = NULL;
|
|
obuf = n->rbuflist;
|
|
|
|
/*
|
|
* In the present incarnation, no more than one buffer can be on
|
|
* the queue; however, we sniff the queue anyway as a hint for
|
|
* further development.
|
|
*/
|
|
if (obuf == NULL) {
|
|
n->rbuflist = rbuf;
|
|
} else {
|
|
while (obuf->next != NULL)
|
|
obuf = obuf->next;
|
|
obuf->next = rbuf;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* ndbeep() - progress indicator
|
|
*/
|
|
void
|
|
ndbeep(
|
|
Node *n,
|
|
Event e
|
|
)
|
|
{
|
|
static int first_time = 1;
|
|
char *dash = "-----------------";
|
|
|
|
if(n->bdly > 0) {
|
|
if (first_time) {
|
|
printf(
|
|
"\t%4c T %4c\t%4c T+ERR %3c\t%5cT+ERR+NTP\n", ' ', ' ', ' ', ' ',' ');
|
|
printf("\t%s\t%s\t%s\n", dash, dash, dash);
|
|
first_time = 0;
|
|
push(event(n->bdly, BEEP), &n->events);
|
|
push(event(n->sim_time, BEEP), &n->events);
|
|
printf("\t%16.6f\t%16.6f\t%16.6f\n",
|
|
n->time, n->clk_time, n->ntp_time);
|
|
return;
|
|
}
|
|
printf("\t%16.6f\t%16.6f\t%16.6f\n",
|
|
n->time, n->clk_time, n->ntp_time);
|
|
push(event(e.time + n->bdly, BEEP), &n->events);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Abort simulation
|
|
*/
|
|
void
|
|
abortsim(
|
|
char *errmsg
|
|
)
|
|
{
|
|
perror(errmsg);
|
|
exit(1);
|
|
}
|